LLVM-1163: AAPCS-VFP violation when CPRC allocated to stack

According to the AAPCS, when a CPRC is allocated to the stack, all other
VFP registers should be marked as unavailable.

I have also modified the rules for allocating non-CPRCs to the stack, to make
it more explicit that all GPRs must be made unavailable. I cannot think of a
case where the old version would produce incorrect answers, so there is no test
for this.

llvm-svn: 200970
This commit is contained in:
Oliver Stannard 2014-02-07 11:19:53 +00:00
parent 6a284eecec
commit 1dc1034218
5 changed files with 69 additions and 11 deletions

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@ -348,6 +348,15 @@ public:
return AllocateStack(Size, Align);
}
/// Version of AllocateStack with list of extra registers to be shadowed.
/// Note that, unlike AllocateReg, this shadows ALL of the shadow registers.
unsigned AllocateStack(unsigned Size, unsigned Align,
const uint16_t *ShadowRegs, unsigned NumShadowRegs) {
for (unsigned i = 0; i < NumShadowRegs; ++i)
MarkAllocated(ShadowRegs[i]);
return AllocateStack(Size, Align);
}
// HandleByVal - Allocate a stack slot large enough to pass an argument by
// value. The size and alignment information of the argument is encoded in its
// parameter attribute.

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@ -89,11 +89,15 @@ class CCAssignToStack<int size, int align> : CCAction {
int Align = align;
}
/// CCAssignToStackWithShadow - Same as CCAssignToStack, but with a register
/// to be shadowed.
class CCAssignToStackWithShadow<int size, int align, Register reg> :
CCAssignToStack<size, align> {
Register ShadowReg = reg;
/// CCAssignToStackWithShadow - Same as CCAssignToStack, but with a list of
/// registers to be shadowed. Note that, unlike CCAssignToRegWithShadow, this
/// shadows ALL of the registers in shadowList.
class CCAssignToStackWithShadow<int size,
int align,
list<Register> shadowList> : CCAction {
int Size = size;
int Align = align;
list<Register> ShadowRegList = shadowList;
}
/// CCPassByVal - This action always matches: it assigns the value to a stack

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@ -114,10 +114,11 @@ def CC_ARM_AAPCS_Common : CallingConv<[
CCIfType<[i32], CCIf<"ArgFlags.getOrigAlign() != 8",
CCAssignToReg<[R0, R1, R2, R3]>>>,
CCIfType<[i32], CCIfAlign<"8", CCAssignToStackWithShadow<4, 8, R3>>>,
CCIfType<[i32, f32], CCAssignToStack<4, 4>>,
CCIfType<[f64], CCAssignToStack<8, 8>>,
CCIfType<[v2f64], CCAssignToStack<16, 8>>
CCIfType<[i32], CCIfAlign<"8", CCAssignToStackWithShadow<4, 8, [R0, R1, R2, R3]>>>,
CCIfType<[i32], CCAssignToStackWithShadow<4, 4, [R0, R1, R2, R3]>>,
CCIfType<[f32], CCAssignToStackWithShadow<4, 4, [Q0, Q1, Q2, Q3]>>,
CCIfType<[f64], CCAssignToStackWithShadow<8, 8, [Q0, Q1, Q2, Q3]>>,
CCIfType<[v2f64], CCAssignToStackWithShadow<16, 8, [Q0, Q1, Q2, Q3]>>
]>;
def RetCC_ARM_AAPCS_Common : CallingConv<[

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@ -0,0 +1,22 @@
; RUN: llc < %s -o - -filetype=asm | FileCheck %s
target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-n32-S64"
target triple = "armv8-none--eabi"
; CHECK-LABEL: fn1:
define arm_aapcs_vfpcc float @fn1(double %a, double %b, double %c, double %d, double %e, double %f, double %g, float %h, double %i, float %j) {
ret float %j
; CHECK: vldr s0, [sp, #8]
}
; CHECK-LABEL: fn2:
define arm_aapcs_vfpcc float @fn2(double %a, double %b, double %c, double %d, double %e, double %f, float %h, <4 x float> %i, float %j) {
ret float %j
; CHECK: vldr s0, [sp, #16]
}
; CHECK-LABEL: fn3:
define arm_aapcs_vfpcc float @fn3(float %a, double %b, double %c, double %d, double %e, double %f, double %g, double %h, double %i, float %j) #0 {
ret float %j
; CHECK: vldr s0, [sp, #8]
}

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@ -185,12 +185,34 @@ void CallingConvEmitter::EmitAction(Record *Action,
else
O << "\n" << IndentStr << " State.getTarget().getDataLayout()"
"->getABITypeAlignment(EVT(LocVT).getTypeForEVT(State.getContext()))";
if (Action->isSubClassOf("CCAssignToStackWithShadow"))
O << ", " << getQualifiedName(Action->getValueAsDef("ShadowReg"));
O << ");\n" << IndentStr
<< "State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset"
<< Counter << ", LocVT, LocInfo));\n";
O << IndentStr << "return false;\n";
} else if (Action->isSubClassOf("CCAssignToStackWithShadow")) {
int Size = Action->getValueAsInt("Size");
int Align = Action->getValueAsInt("Align");
ListInit *ShadowRegList = Action->getValueAsListInit("ShadowRegList");
unsigned ShadowRegListNumber = ++Counter;
O << IndentStr << "static const uint16_t ShadowRegList"
<< ShadowRegListNumber << "[] = {\n";
O << IndentStr << " ";
for (unsigned i = 0, e = ShadowRegList->getSize(); i != e; ++i) {
if (i != 0) O << ", ";
O << getQualifiedName(ShadowRegList->getElementAsRecord(i));
}
O << "\n" << IndentStr << "};\n";
O << IndentStr << "unsigned Offset" << ++Counter
<< " = State.AllocateStack("
<< Size << ", " << Align << ", "
<< "ShadowRegList" << ShadowRegListNumber << ", "
<< ShadowRegList->getSize() << ");\n";
O << IndentStr << "State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset"
<< Counter << ", LocVT, LocInfo));\n";
O << IndentStr << "return false;\n";
} else if (Action->isSubClassOf("CCPromoteToType")) {
Record *DestTy = Action->getValueAsDef("DestTy");
MVT::SimpleValueType DestVT = getValueType(DestTy);